Recently developed combination tillage implements have employed disk blades with individually mounted bearing blade assemblies which are able to run in wetter fall soil conditions. Many of the combination tillage implements include bulky C-spring standards supporting angled gang tubes which meet in at the implement center. The C-springs are angled toward one another, and mounting requirements for the springs force the center blades to be more widely spaced than desired. The wide spacing of the center blades results in an inadequate cut of the soil at the center of the machine. The center disk spacing problem typically is overcome either by employing a special standard bearing assembly to mount two disk blades or by utilizing an intermediate short gang tube in the middle to carry the two disk assemblies. Both solutions require a costly weldment or assembly.
The disk blade bearings are subjected to high loads in a severe environment. Bearing seal failure leading to premature bearing failure has been an ongoing problem. For years, the main attempt at a solution to the problem has been the utilization of a grease fitting with frequent scheduled greasing to flush contaminates out of the bearing. For most disk gang bearing applications, frequent greasing has been a generally acceptable practice since each bearing normally supports from three to six blades and the grease fittings are reasonably accessible. However, the frequent greasing is time-consuming and reduces the productivity of the implement. Machines with individually mounted blades create two new problems relative to the grease method of flushing the bearings. First, wetter field conditions are harder on the seals. Mud packs into the seal area and ultimately works into the bearing to cause permanent damage to the seals.
To overcome the mud problem, the frequency of required re-greasing to flush the contaminates and prevent bearing failure has to be increased. The individually mounted blade bearing assemblies result in more bearings to carry the same number of blades as a disk gang. The combination of more grease fittings to grease and an increased maintenance frequency results in a difficult time-consuming maintenance chore. In addition, the mounting requirements for the C-springs force the center blades to be more widely spaced than desired adjacent the juncture of the angled tubes supporting the C-springs results in an uneven tillage pattern near the center of the machine.